CPU: AMD phenom ii x4 965 Black edition
Motherboard: ASUS M4A785TD-V EVO
Graphics: ATI Radeon 5850
Ram: Kingston DDR3 6GB 1333 value ram
Hard Drive: Seagate Barracuda 750GB 7200rpm 32md cache
Power Supply: Antec Basiq 550W ATX Power Supply
Using it mainly for gaming and probably not going to overclock
You're proably not in the US, are you? If you are, you're getting screwed on the price...
Ignoring the budget, I have several changes.
First, switch the CPU to a X4 955. It's basically the same, but cheaper because it doesn't have a factory overclock.
Second, switch the board for an Gigabyte GA-770TA-UD3 (no Crossfire) or Gigabyte GA-790XTA-UD4 (with Crossfire). These are much more future proof.
Third, you're buying the wrong RAM. You need dual channel sticks (i.e. two 2 GB sticks) not triple channel. Get a good set of either 1333 mhz or 1600 mhz sticks with CAS Latency 7.
Fourth, that HDD is going to be slow. You want to get the Seagate 7200.12 500 GB or 1 TB model, not the 750 GB. Or get a Samsung Spinpoint F3 in the same two sizes (500 GB or 1 TB).
Fifth, that PSU isn't that great, but it's passable. I'd definitely consider getting an Earthwatts unit from Antec. If you're planning on Crossfire, you'll need at least a 650W unit if you don't mind using power adapters.